Telephone wires are generally of 24 or 26 gauge AWG wire and are provided in pairs, one of the wires in the pair being the "tip" wire and the other being the "ring" wire. In the United States of America, for example, telephone cables are provided with 25 pairs of wires or multiples thereof. Telephone wire connectors designed for use in the United States of America are, therefore, generally made to connect 25 pairs of wires.
One standard type of telephone cable connector comprises a female connector and a mating male connector. The female connector is formed on one surface with a recess having generally vertical interior side walls along which wiping contacts are arranged, the contacts being exposed on the opposite surface for making connection to the wires of a cable. The male connector is formed on one surface with a central rib having generally vertical sidewalls along which wiping contacts are arranged complementary to the wiping contacts on the female connector. The contacts on the male also extend through the opposite surface of the male connector for connection to the wires of the cable. Such connectors are, for example, disclosed in U.S. Pat. Nos. 3,277,426; 3,599,172; 3,657,682 and 3,760,335. The construction of such connectors has generally required that they be wired in two parallel rows generally perpendicular to the wiring surfaces of each of the male and female connector, making it extremely difficult to wire such connectors in series where multiple connections to a single cable are desired.
Telephone cable connectors having wire stripping contact elements in parallel channels have previously been taught, for example in U.S. Pat. No. 3,708,779, and they are in widespread use because of their greater ease of application. However, the wire spacing in the standard male-female telephone cable connector is too close to permit the use of the cable connector of U.S. Pat. No. 3,708,779 due to the interference of the contact element with the wires on either side of the one it is connecting. The contact elements cannot simply be made narrower since they become too weak to make effective spring compression reserve contact with the wires.
A standard male-female telephone cable connector overcoming these problems is disclosed in U.S. application Ser. No. 630,220, filed concurrently herewith. That connector has an insulating body formed on one surface with a plurality of parallel wire support channels, each of the channels being formed with a transverse step defining upper and lower wire support levels. The adjacent channels are formed with steps rising from generally coplanar lower wire support levels to generally coplanar upper wire support levels in opposite directions lengthwise of said channels to position a lower wire support level between two upper wire support levels. A cover is formed on one surface with parallel stepped wire support channels complementary to the channels on the base to press wires into spring compression reserve contact elements in the lower wire support levels of the insulating body to make electrical connection to the wires.
The upper wire support levels raise the wires adjacent the contact element above the contact element to prevent their interference. The walls of the upper wire support levels bounding a lower support level back up the legs of the spring compression reserve contact element in the lower support level increasing the effectiveness of the electrical connection it makes thereby permitting use of narrower contact elements than can be used when they are free standing. Both the raising of the wires on the upper support levels and the use of narrower contact elements which are backed by the sidewalls of the upper support levels permits closer wire spacing so that the wire spacing in the standard female-male telephone wire connector can be used. Furthermore, the use of the complementary stepped body and cover provides the necessary strain relief.